grandfather vs patriarch

grandfather

noun
  • A male forefather. 

  • A father of someone's parent. 

  • The archived older version of a file that immediately preceded the father file. 

verb
  • To retain discontinued laws or rules for (a thing, person or organization previously affected by them). 

  • To be, or act as, a grandfather to. 

patriarch

noun
  • The male head of a household or nuclear family. 

  • A founder of a political or religious movement, an organization or an enterprise. 

  • An old leader of a village or community. 

  • The male progenitor of a genetic or tribal line, or of a clan or extended family. 

  • The highest form of bishop, in the ancient world having authority over other bishops in the province but now generally as an honorary title; in Roman Catholicism, considered a bishop second only to the Pope in rank. 

  • In Biblical contexts, a male leader of a family, tribe or ethnic group, especially one of the twelve sons of Jacob (considered to have created the twelve tribes of Israel) or (in plural) Abraham, Isaac and Jacob. 

How often have the words grandfather and patriarch occurred in a corpus of books? (source: Google Ngram Viewer )